package com.test;

import lombok.extern.slf4j.Slf4j;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.text.PDFTextStripper;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

@Slf4j
public class DownloadPdf {

    /**
     * 从网络Url中下载文件
     *
     * @param urlStr
     * @param fileName
     * @param savePath
     * @throws IOException
     */
    public static void downLoadByUrl(String urlStr, String fileName, String savePath) throws IOException {
        URL url = new URL(urlStr);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        //设置超时间为3秒
        conn.setConnectTimeout(5 * 1000);
        //防止屏蔽程序抓取而返回403错误
        conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
        //得到输入流
        InputStream inputStream = conn.getInputStream();
        //获取自己数组
        byte[] getData = readInputStream(inputStream);
        //文件保存位置
        File saveDir = new File(savePath);
        if (!saveDir.exists()) {
            saveDir.mkdir();
        }
        File file = new File(savePath + "/" + fileName); // File.separator
        log.info(file.getAbsolutePath());

        file.createNewFile();
        FileOutputStream fos = new FileOutputStream(file);
        fos.write(getData);
        if (fos != null) {
            fos.close();
        }
        if (inputStream != null) {
            inputStream.close();
        }
        System.out.println("info: " + url + " download success");

    }


    /**
     * 从输入流中获取字节数组
     *
     * @param inputStream
     * @return
     * @throws IOException
     */
    public static byte[] readInputStream(InputStream inputStream) throws IOException {
        byte[] buffer = new byte[1024];
        int len = 0;
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        while ((len = inputStream.read(buffer)) != -1) {
            bos.write(buffer, 0, len);
        }
        bos.close();
        return bos.toByteArray();
    }

    /**
     * 传入一个.pdf 地址
     *
     * @param pdfUrl 地址
     * @throws Exception
     */
    public static void readPdf(String pdfUrl) throws Exception {
        // 是否排序
        boolean sort = false;
        // 编码方式
        String encoding = "UTF-8";
        // 开始提取页数
        int startPage = 1;
        // 内存中存储的PDF Document
        PDDocument pdDocument = null;
        //输入流
        InputStream inputStream = null;
        try {
            try {
                // 当作一个URL来装载文件
                URL url = new URL(pdfUrl);
                URLConnection con = url.openConnection();
                con.setConnectTimeout(10 * 1000);
                inputStream = con.getInputStream();
                pdDocument = PDDocument.load(inputStream);
            } catch (MalformedURLException e) {
                e.printStackTrace();
            }

            // 获取页码
            int endPage = pdDocument.getNumberOfPages();
            PDFTextStripper stripper = null;
            stripper = new PDFTextStripper();
            // 设置是否排序
            stripper.setSortByPosition(sort);
            // 设置起始页
            stripper.setStartPage(startPage);
            // 设置结束页
            stripper.setEndPage(endPage);
            System.out.println(stripper.getText(pdDocument));
            System.out.println(" 输出成功！");
        } finally {
            if (inputStream != null) {
                // 关闭输出流
                inputStream.close();
            }
            if (pdDocument != null) {
                // 关闭PDF Document
                pdDocument.close();
            }
        }
    }

    public static void main(String[] args) {
        try {
            readPdf("http://dubbo.apache.org/zh-cn/docs/user/references/xml/dubbo-protocol.html");
//            downLoadByUrl("http://dubbo.apache.org/zh-cn/docs/user/references/xml/dubbo-protocol.html", "ELISA.pdf", "D:");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}